TEIID LIZARDS OF THE GEXUS CXEMIDOPHORUS 



253 



position ill the family Teiidao. soinewheie between the obviously 

 specialized genera on the one hand and the more generalized, includ- 

 ing Ameiva. on the other. This relationship is expressed in the dia- 

 gram, Figure 36. 



The particular problems of the present study are those concern- 

 ing the evolutionary relationships within the genus Cncmidopliorus. 

 This genus comprises five distinct groups of related forms, called 

 in this Avork the lemniscatU'S, deppii, sexlineatiis, tessellatus, and 

 hyperythrus groups. Only one of these, the JemniscatuH grouj), is 

 closely related to the ancestral genus Ameiva. and of this group, 



Specieilize 



TieTT>\ 



xdopVi 



orus 



TupinaTnlp-is 



CQ.\lop\stes 



Ne-usKcur-us 



Croeodi'l'urus 

 Drac^erva. 



Ancestor of 

 Gro-upH 



Ancestor of 

 Group I 



Ancestral Stock o^ tV\e TeWdae 



Figure 30. — Diagisa.m of the slti'used kelatioxships of the fiu.mitive Teiidae 



but one form, murinus^ shows a close relationship to an Ameiva 

 {A. ameiva ameiva). This relationship is shown in murlnus (as 

 compared with other CnemidophoH) in the greater number of longi- 

 tudinal rows of ventral and caudal plates, in the smaller size of 

 the brachials, in the presence of a patch of enlarged postbrachials, 

 in the possession of five parietal shields, in the retention of a ves- 

 tigial sheath between the larnyx and the posterior tips of the scaly 

 portion of the tongue, in the opening of the nostril between the 

 anterior and posterior nasal shields, and in the similarity of th;- 

 spotted pattern of the adults. All of these are variations or condi- 



